Re-evaluate the pathmap if there's a recovery variant in play

Chances are the recovery location has changed, so rebuild the pathmap
to compensate. This lets the variable be defined in BoardConfig files
instead of the global environment

Change-Id: I87c23a452656ffa7817711796c17f79e30465756
(cherry picked from commit 6b21727ef8997762d83691cb453aa950aa8d574b)